mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2026-09-22 09:34:56 +02:00
Injae Ryou
e91d66e5ff
commit98df164036upstream. run_vmtests.sh runs on-fault-limit as the nobody user via "sudo -u nobody ./on-fault-limit", guarded by a check that nobody can access the binary ("sudo -u nobody ls ./on-fault-limit"). The guard resolves the relative path from the inherited working directory, which only requires search permission on the test directory itself. Classic sudo passes the relative path through to execve() the same way, so the two agree. However, sudo-rs (the default sudo implementation since Ubuntu 25.10) canonicalizes the command to an absolute path before executing it, which requires search permission on every ancestor directory. When the kernel tree lives under a private home directory (mode 0750, the Ubuntu default for new users since 21.04), the guard passes but the execution fails with "command not found", and the test is reported as a false FAIL: # running sudo -u nobody ./on-fault-limit sudo: './on-fault-limit': command not found # [FAIL] Wrap the command in "sh -c" so that sudo only resolves the shell binary, and the relative path is resolved by nobody's shell from the inherited working directory, matching what the guard checks. This is the only "sudo -u nobody" invocation in the script; uid, cwd, rlimits (including RLIMIT_MEMLOCK, which this test exercises) and the exit status are unchanged through sh. Verified on Ubuntu 26.04 (sudo-rs 0.2.13): the test now runs and passes instead of failing. Verified on Ubuntu 24.04 (sudo 1.9.15p5): behavior is unchanged. Link: https://lore.kernel.org/20260713092700.464376-1-injaeryou@gmail.com Fixes:5d2146a335("selftests/mm: skip mlock tests if nobody user can't read it") Signed-off-by: Injae Ryou <injaeryou@gmail.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Brendan Jackman <brendan.jackman@linux.dev> Cc: David Hildenbrand <david@kernel.org> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.